of croydon



March 24, 1931. I G, CREED ET AL 1,797,718

ELECTRIC CONTACT MAKING AND BREAKING DEVICE Filed Dec. 12, 1928 PatentedMar. 24, 1931 UNITED STATES PATENT OFFICE FREDERICK GEORGE CREED ANDAXEL ORLING, OF CROYDON, ENGLAND, ASSIGNORS TO CREED AND COMPANYLIMITED, OF CROYDON, ENGLAND ELECTRIC CONTACT MAKING AND BREAKING DEVICEApplication filed December 12, 1928, Serial No. 325,633, and in GreatBritain December 20, 1927.

This invention relates to means of the kind whereby a movable bodyactuated by weak electric forces, can be used for making and breakingelectrical connection between two conductors for bringing into actionsome electrical device, as for instance a thermionic valve, or asensitive relay, for effecting some useful purpose.

To this end, it has been proposed to cause a movable conductor adaptedto be actuated by a weak electrical force, to make contact with astationary conductor or conductors in the form of a stretched or freewire or wires. Also, it has been proposed to c ause two movableconductors actuated alternately in opposite directions by weak positiveand negative signals or charges, to make -contact alternately with twostationary stretched wires. In each of these cases, im-' perfect contactis sometimes produced between the movable conductor or conductors andthe fixed Wire or wires, due to the resilience of the wire or wires,which causes the movable conductor or each movable conduc-' tor, afterbeing momentarily brought into contactwith the associated wire, torebound suddenly therefrom. Sparking and sticking of contacts alsosometimes occur.

An object of the present invention is to provide a contact making andbreaking device wherein the movable conductor or each movable conductor,when moved into electrical connection with its associated stationaryconductor, will not reboundtherefrom,

but will, on the contrary remain infirm contact therewith untilpositively moved therefrom so that the above named disadvantages of theknown arrangements shall be avoided.

For this purpose in a circuit making and breaking device constructedaccording to the present invention, the stretched wire, or eachstretched wire, of the known arrangements, is replaced by a conductorconsisting of a piece of soft non-resilient material having a moistconducting surface. By this means, when the movable conductor is broughtinto contact with the moist surface of the soft non-resilient stationaryconductor, it will not rebound therefrom but will, on the contrary, beheld in effective contact therewith. by reason of the moisture presentcausing adhesion between the two conductors until the movable conductoris positively moved away from the stationary moist conductor. In thisway, a continuous and effective connection can be maintained between thetwo conductors for any desired time.

The moist soft-non-resilient stationary conductor. (hereinafter calledfor brevity the moist conductor) can be variously constituted. Thus, itmay consist of a small pad of porous material mounted upon a suitablesupport and moistened with a conducting liquid, for instance water, inany convenient way, as by capillary action, a part of the said materialdipping for this purpose into liquid contained in a receptacle carryingthe support and pad. Or, as is preferred, the moist conductor consistsof a length of thread, string or like material kept in a taut conditionand moistened with a conducting material. Two more lengths of suchmaterial may sometimes be used. The movable conductor may consist of alength of stiff wire. Two or more of such conductors may be used withone or more moist conductors and be operated in various ways by a devicesub ject to the action of weak electric forces.

In the accompanying illustrative drawings, Figs. 1 to 5 inclusive show,diagrammatically, various arrangements of electric contact making andbreaking devices, embodying the invention. a

In the example shown in Fig. 1, the moist conductor consists of a length1 of thread or string that is'kept in a stretched condition and issupplied with conducting liquid 3 from a small cell or receptacle 4therefor so that it will continually be kept in a moist condition. 5 isa movable conductor, consisting of a length of stiff wire, adapted tocoact with the moist conductor 1.

IVhen weak electric forces are to beutilized, that act alternately inopposite directions, as for example weak positive and negative signalsin land or submarine telegraph lines or cables, a single movableconductor 5 responsive to such signals may be arranged to move to andfro between two moist conductors 1, Pas shown in Fig. 2. Or twooppositely movable conductors 5, 5 adapted to be actuated by theoppositely acting electrical forces may, as shown in Fig. 3, beassociated with two separate moist conductorsl, 1 of the kind describedand to and from which they are respectively moved for the purpose ofmaking and breaking electric connections between them.

When using a piece of thread or string as described, it may, as shown inFig. 1, be connected at one end to the receptacle 4 containing theliquid 3, and at its other end to a bent over portion 6 of a stem 6 ofresilient wire fixed to the receptacle 4, the lower end of the stringbeing in contact with the conducting liquid 3 so that the whole lengthof the string will be wetted by capillary action, whilst it will be heldin a stretched or taut condition by the bent over portion 6 of the pieceof wire, acting as a spring. If two lengths of string be used, theirupper ends may, as shown in Fig. 3 be connected to two bent over springportions 6*, 6 of wire carried by a single stem 6, or it may be byseparate stems.

The movable conductor or conductors may be moved towards and against thestationary moist conductor or conductors by a returning force, forinstance a spring or springs, and be moved away from the moist conductoror conductors by a weak electrical force or forces, against the actionof the returning force, which acts to return it or them to the moistconductor or conductors when the electrical force ceases to act, or toact with insufficient force to overcome the returning force.

The electrical device subject to weak electrical forces and used formoving the movable conductor or conductors away from the moist conductoror conductors may for example, be a coil that is subject to the actionof weak electrical currents or charges and is suspended in a permanentmagnetic field formed between the oppositely arranged north and southpoles of a permanent magnet, as in telegraphic apparatus used With asubmarine cable and siphon .recorder the coil being normally held in amid-position by torsion means and provided with a light arm foractuating the movable conductor or conductors in accordance withelectrical, signals received by such coil.

Contact making and breaking devices with associated controlling meansand controlled means, according to the invention, can be variouslyconstructed and arranged to suit different requirements.

Fig. 4 shows by way of example, one arrangement compgising two springcontrolled movable conductors 5, 5 connected to the re- I spective gridsof two thermionic valves 7 and 8 and arranged to co-act with twostationary moist conductors 1, 1" connected to the grid circuits of thevalves through a grid bias battery 9, the two movable conductors beingarranged to be moved alternately from their respective moist conductorsby an arm tween the grids of the two valves and the battery 9. The twothermionic valves 7 and 8 may be arranged to actuate means, for instancerelays 13 and 14,. The arrangement is such that when the conductor 5 ismoved away from the moist conductor 1 by the arm 7 under the act-ion ofsay a positive signal or impulse traversing the coil 10, the thermionicvalve 7 will act to cause its associated relay 13 to reproduce or recorda corresponding positive signal and when the movable conductor 5 ismoved away from the moist conductor 1 by a negative signal or impulse,the corresponding thermionic valve 8 will act to cause its associatedrelay 12 to reproduce or record a corresponding negatlve signal.

Each movable conductor 5 and 5 may, as more clearly shown in Fig. 5 berigidly connected to but insulated from a straight length 15 of wirearranged at right angles to it and fixed atits ends 15", 15", each suchlength of'wire including a torsion spring 16 adapted to move theconductor 5 or 5 towards and against its corresponding moist conductor 1or 1 when the movable arm 7 permits it to do so.

We claim: g 1. An electric contact making and breaking device comprisina conductor of non-resilient material having a moist conducting surface,a metal conductor, and means for mov ingthe said conductors into and outof contact. 1

2. An electric contact making and breaking device comprising a conductorof non-resilient material, means for keeping the said con ductormoistened, means for holding the said conductor taut, a metal conductorand means for moving the said conductors into and out of contact.

3. An electric contact making and breaking device comprising a vesselcontaining a conducting liquid, a thread supported above and extendinginto said liquid, :1. metal conductor and means for moving said metalconductor into and out of contact with said thread.

4. An electric contact making and breaking device comprising a vesselcontaining a conducting liquid,,two threads separately supported andextending intosaid liquid, two metal conductors and means for moving one'metal conductor into contact with one thread, and the other metalconductor out of contact with the other thread, or vice versa.

5. In a thermionic relay, comprising in combination, an electriccontactmaking and breaking .device containing a conducting liquid a threadextending into said liquid, a metal conductor, a space discharge devicewarms having an input circuit and an output circuit, electric circuitleads connecting said thread and said metal conductor to the inputcircuit of said space discharge device, means for moving said metalconductor into and out of contact with said thread, and means in theoutput circuit of said space discharge device for recording saidmovement.

6. In a thermionic tube relay, comprising in combination, an electriccontact making and breaking device comprising a vessel containing aconducting liquid, two threads extending into said liquid, means forkeeping both of said threads taut, two space discharge devices eachhaving an-input circuit containing a resistance and an outputcircuit,electric circuit leads connecting said conducting liquid to one terminalof each resistance, two metal conductors, electric circuit leadsconnecting said conductors to the other terminals of the respectiveresistances,

means for moving the metal conductors into or out of contact with therespective threads, and means in the output circuit of said spacedischarge devices for recording the move-' ment of said metalconductors.

7. In combination, moist and dry conductors, means for moving saidconductors relatively into and out of contact, a recording device andmeans for rendering said recording device operative upon opening of saidcontact.

8. in combination, moist and dry conductors, impulse responsive meansfor mov-- ing said conductors relatively into and out of contact, arecording device and space discharge means for actuating said recordingdevice.

9. In combination, impulse responsive means, spaced moist conductors, amovably disposed dry conductor associated with each moistened conductor,means operated by said impulse responsive means for alternatelyactuating said movable conductors to contact,

their associated moist conductor, a thermionic device associated witheach moist and dry conductor, normal biasing and actuating electromotiveforces, grid leaks in multiple with said electromotive forces, a platecircuit and means disposed in said circuit for recording impulses ofopposite polarities traversing said impulse responsive means.

10. In combination, signal responsive means, means carried thereby foropening or closing a contact comprising a moist and dry portion, spacedischarge means, impulse recording means operatively associated withsaid space discharge means, means responsive to the opening of saidcontact for actuatin said discharge device to render operative sairecording means.

11. In combination, means, means carried thereby for opening or closinga contact, the latter comprising a wet conducting portion and dryconducting signal responsive nately whereby an impulse through saidsignal responsive means is repeated by said recording means. v

13. An electric contact making and breaking device comprising aconductor having a moist conductor surface, a metal conductor, and meansfor moving the said conductors into and out of contact.

14:. An electric contact making and breaking device comprising aconductor, means for keeping the said conductor moistened, means forholding the said conductor taut, a metal conductor and means for movingthe said conductors into and out of contact.

In witness whereof, we hereunto subscribe out names.

FREDERICK GEORGE CREED. AXEL ORLING.

